# coding:utf-8

import  pandas as pd
import lxml


df = pd.read_csv("C:\\Users\\ljb\\Desktop\\catering_sale.csv",header=0)

print(df[df.isnull().values == True])

print(df.fillna(0))
print(df["sale_amt"].fillna(df["sale_amt"].count()))

print(df.fillna(method="pad"))